1. Technical Field
The present disclosure relates to a conductive ball mounting apparatus and a conductive ball mounting method and, more particularly, a conductive ball mounting apparatus and a conductive ball mounting method for mounting conductive balls on a substrate such as a wiring substrate, a wafer, or the like having a plurality of pads on which an adhesive is formed thereon.
2. Background Art
FIG. 1 to FIG. 6 are step views describing a conductive ball mounting method in the related-art.
A conductive ball mounting method in the related-art will be described with reference to FIG. 1 to FIG. 6 hereunder. At first, in steps shown in FIG. 1, a flux 102 is formed on a plurality of pads 101 provided on a substrate 100, and also a resist film 103 is formed on portions of the substrate 100 positioned between a plurality of pads 101.
Then, in steps shown in FIG. 2, the mask 106 having a plurality of openings 106A is fixed on the resist film 103. The openings 106A are formed to expose the pads 101.
Then, in steps shown in FIG. 3, a plurality of conductive balls 108 are disposed on the mask 106. Then, in steps shown in FIG. 4, one conductive ball 108 is mounted on the pads 101 on which the flux 102 is formed respectively by vibrating the substrate 100.
Then, in steps shown in FIG. 5, extra conductive balls 108 that have not been mounted on the pads 101 are removed by sweeping an upper surface of the mask 106 by a squeegee 110. Then, in steps shown in FIG. 6, the mask 106 is removed. Accordingly, the substrate 100 having the conductive balls 108 on the pads 101 is formed (see e.g., JP-A-11-297886).
However, in the method of mounting the conductive ball 108 in the related-art, the step of mounting one conductive ball 108 on the pads 101 on which the flux 102 is formed respectively and the step of removing the extra conductive balls 108 by sweeping an upper surface of the mask 106 by the squeegee 110 are performed separately. Therefore, such a problem existed that it is difficult to improve productivity in the step of mounting the conductive ball 108 on the pads 101 and the step of removing the extra conductive balls 108.
In addition, Japanese Patent Application Publication: JP-A-2-102538 discloses another conductive ball mounting method. In JP-A-2-102538, a conductive layer on which a solder bump is formed is formed on one surface of a circuit substrate and also a solder-flux layer is formed on the one surface of the circuit substrate. Then, a spacer is formed on the solder-flux layer and a mask having openings is formed on the spacer. Next, the circuit substrate is disposed on a solder ball container for accommodating solder balls such that the one surface of the circuit substrate opposes to an opening formed in the solder ball container. Finally, the solder balls are mounted on the circuit substrate by vibrating the solder ball container hard (see FIG. 1 of JP-A-2-102538).
However, in the conductive ball mounting method disclosed in the related-art, rapid vibration is required to mount the solder balls on the openings of the mask. In this case, force caused by the rapid vibration is also applied to the circuit substrate (the mask). Especially, upon using a large substrate, a thin substrate or small balls whose diameter is 100 μm or less, thickness of the mask becomes thin and thus the mask is more likely to vibrate. Therefore, defect such as displacement of the solder balls is generated by vibration of the mask (the circuit substrate).